[LAU] jack/oversampling

[Gene Heskett]

On Sunday 16 March 2014 19:56:32 Ralf Mardorf did opine:

> Gene :)
> 
> ok, when I've got the time to do it, I will borrow the Brauner VM-1 tube
> mic + an ART tube pre amp from a friend, connect it directly to my RME
> HDSPe AIO and pick Blackbird from the Beatles on my classical guitar and
> do a recording at 48 KHz and 192 KHz.
> 
> I don't know what will happen, but I suspect there will be no audible
> difference.
> 
> Regards,
> Ralf
> 
> 
Even with tons of string squeaks from wound strings and heavily callused 
fingers, I doubt if that would reach high enough to be a valid test.  You 
need a few crickets singing in the background, (typically 17 Khz) and some 
heavy action on a brushed snare drum to generate very much in the range of 
sound that would test it for sure.  A "white noise" generator made out of 
the usual 17 stage xor gated shift register for feedback, clocked at 50Khz 
or more might be a good test, the white noise will seem to have a odd, 
often disagreeable, definitely non-harmonious pitch to it.

But I haven't seen that schematic in yonks.  Take a look at

<http://en.wikipedia.org/wiki/Linear_feedback_shift_register>

Some of the longer ones are pretty decent. the 17th register addition is 
one I heard once, sounded pretty white to my ears at the time.

Cheers, Gene
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